. >>> don wright isn't going to let a little thing like cancer keep him from his goal. that's running a marathon in every state. he's well on his way. he's an unusual patient in another way, experimenting with a new approach to his disease. here's dr. sanjay gupta with today's "human factor." >> don wright's career spanned engineering, being a company vice president, and the law. and at age 62, he discovered a new passion -- marathons. eight years ago, just days after running his first 26-mile race, though, he got some devastating news. >> i'd gone to the doctor a couple times for pain in my back. it was multiple myeloma. >> reporter: this is a cancer of the blood where the white blood cells invade the bone marrow causing pain, lususually in the back or the rib, and patients are rarely cured. but right refused to let that slow him down, even qualifying for the boston marathon. >> i got this devastating diagnosis and we just -- my family and i, we just kept on going. you know, there wasn't any reason to stop and be sorry, you know. we kept running marathons. >> reporter: